Plant extract mixtures and their uses

ABSTRACT

A composition comprising extract of one or more plants of one or more of the following plant families:  Cissus, Vernonia  and  Brillantasia . Such compositions have beneficial activity principally in controlling weight gain and obesity, especially in conjunction with chitosan or a chitosan derivative and an antioxidant such as vitamin C.

This invention is concerned with mixtures comprising plant extracts from plants in at least one of three families (one or more of Cissus, Vernonia and Brillantasia), and uses of the mixtures to enhance fat-binding capacity as well as the inhibition of carbohydrate breakdown, amylase activity and nutrient absorbtion in the presence of fat binding materials. In particular the mixtures can be combined with chitosan or chitosan derivatives to synergise their fat binding properties.

Fat binding materials e.g. chitosan have applications in industry and in health. In both cases, the binding capacity of these materials is limited because of their bulk. The new combination of plant extracts has the ability to enhance the fat binding capacity of such materials as well as alter the metabolism of other compounds in animals, including humans.

Chitosan is widely used for the control of weight. Its use is based on its ability to bind fatty acids in vitro and in vivo, thereby reducing the ability of the body to absorb and utilise dietary fats. By combining chitosan with two plant extracts; Cissus quandragularis and Veronia glabra, its ability to bind fatty acids and triacylglycerols in vitro was significantly increased (p<0.05 and p<0.01 respectively). This is reflected in the significantly higher fat content of the faeces of subjects on chitosan or chitosan based formulations. Compared to chitosan, the combination of chitosan and Cissus quadrangularis significantly increased the fecal pH (p<0.01), fecal ash (p<0.02) and mineral content (p<0.02) in overweight women (BMI 25–29 kg/m²) over a six month period, while decreasing the fecal water content (p<0.01) the combination of chitosan and Vernonia glabra did not alter the mineral content or the pH of the faeces although it caused a significant increase (p<0.05) in fecal bulk. The results indicate that the chitosan and Vernonia glabra combination can be effectively used in long term weight control regimes.

Chitosan is a polysaccharide produced from chitin found in the exoskeletons of arthropods (crustaceans and insects) and the endoskeletons of cephalopods. It is widely spread in the biomass, being the most abundant biopolymer after cellulose. It is generally accepted that chitin is extensively acetylated while chitosan is largely deacetylated. Chitosan is a cationic glucosamine polymer with a high anion-exchange capacity as a result of quaternary ammonium ions. It is known to have a marked hypocholesterolemic effect in rats, alters bile acid metabolism and increases HDL:total cholesterol ratio in broiler chickens. The hypocholesterolemic effect of chitosan can be theoretically explained by its ability to decrease lipid absorption and increase fecal cholesterol excretion. The alteration of bile acid can be due to the modification of colon pH.

Chitosan is widely used in weight control products. Its application is a result of its ability to bind triglycerides in vitro. In principle therefore, chitosan limits the amount of fat energy that can be absorbed and used by the body. The use of chitosan therefore does not find application only as a weight loss supplement, but also as a means of reducing blood lipids.

We have investigated the effect of chitosan and chitosan based formulations on overweight women. Their BMI and body composition had been evaluated. The fecal weight, fecal pH, water content, calcium and magnesium content and total nitrogen were measured. The total blood lipid content and beneficial effects of plant supplements (extracts of Vernonia glabra and Cissus quadrangularis) on improved chitosan lipid binding has unexpectedly been found.

According to one aspect of the present invention there is provided a composition comprising extract of one or more plants of one or more of the following plant families: Cissus, Vernonia and Brillantasia. According to another aspect the invention provides uses of such compositions in treating disease or disorder, in particular for preventing, controlling or combatting obesity. In another aspect the invention provides such compositions for the preparation of a medicament for use in treating any of the ailments or conditions herein described.

The composition preferably comprises or essentially consists of a mixture of at least two of the said plant extracts. The composition preferably also include one or more fat binding materials such as chitosan or a chitosan derivative, one or more amylase inhibiting compounds and/or one or more antioxidants such as vitamins A, C, or E.

The plant extracts are usefully obtained from dried or freeze dried plant components.

The extract may be of the leaves, roots and/or stem of the plants. The extract may be dried powder or entirely aqueous-derived such extract, e.g. obtained by boiling the plant components in water, or derived from a mixture containing water and, for example, ethanol. A mixture of water and 50% by volume of ethanol is suitable and preferred. The extracts are also preferably ion exchange unbound and resin scavenged prior to use and formulation with chitosan or chitosan derivative. It is possible, but less preferred to use extracts derived from the solvent dichloromethane.

Preferably in the case of plants of the Cissus family the plant components used in making the extract are the leaves, roots and/or stem. Preferably the extracts are aqueous and can be produced by a simple, conventional extraction technique, although it is more preferable that the plant components be dried before addition of water and boiling the mixture.

Such compositions can be formulated for human consumption and can demonstrate one or more of the following other properties:

(1) Reduces the amount of fat absorbed by the body,

(2) Increases the amount of fat in faeces,

(3) Increases faecal bulk,

(4) Reduces carbohydrate breakdown in vitro,

(5) Reduces carbohydrate breakdown in vivo,

(6) Inhibits salivary amylase activity,

(7) Inhibits intestinal amylase activity,

(8) Decreases the acidity of the stomach,

(9) Increases the amount of cholesterol in faeces,

(10) Reduces post-prandial blood glucose,

(11) Inhibits intestinal lipase activity,

(12) Reduces the body mass index (weight) of subjects.

EXAMPLE 1

Preparation of the Mixture

Plants of the Cissus family, Vernonia family, and Brillantasia family:

Plant component used: Leaves, stems and roots

Preparation Method:

The leaves, stems and roots are dried at 45° C. for 72 hours. The dried samples are transferred into 2 times their weight of water and boiled for 1 hour. The mixture is left to stand for 2 hours at room temperature before straining to remove any residue. The resultant supernatant is stored at 4° C. until required.

Brillantasia sp.

Plant component used: Leaves

Preparation Method:

The leaves are harvested from the plant and dried at 45° C. for 72 hours. The dried leaves are finely ground into a powder, then transferred into 2 times their weight of boiling water. This is left to stand for two hours at room temperature before straining to remove leaf residue. The resultant supernatant was stored at 4° C. until required.

Cissus sp. and Vernonia sp. Combination

Although all combinations of extracts of plants of the three families, namely Cissus sp. Vernonia sp. and Brillantasia sp. had an enhancing effect, optimal activity was obtained using the following mixture of two aqueous plant extracts:

Cissus sp extract 50–90%, more preferably 60–80% most preferably 70% (v/v)

Vernonia sp. 10–50% more preferably 20–40% most preferably 30% (v/v)

This is a preferred specific mixture of Cissus sp. and Vernonia sp.,

Application and Dose

The mixture can be taken orally at a concentration of 0.1 to 10 ml, preferably 0.1 to 5 ml, more preferably 0.2 to 2 ml, most preferably 0.5 ml per kilogram body weight with or before a meal.

EXAMPLE 2

Plant Materials

Vernonia glabra (root) and Cissus quadrangularis (leaf and stem) were harvested from the Western and Centre Provinces of Cameroon respectively. The plant material was washed and dried for three days in an oven at 55° C. The dried material was then ground, seived and stored until required. Chitosan based formulations were made as shown in Table I (increasing concentration of plant extract and decreasing chitosan content)

TABLE 1 Composition of different chitosan based formulations Chitosan formulations Constituents (mg) CF₀ CF₁ CF₂ CF₃ CF₄ Chitosan 250 200 170 150 100 Vitamin C 60 60 60 60 60 Plant powder 0 50 80 100 150 In Vitro Binding Studies

The ability of various chitosan combinations to bind triacylglycerol was carried out as described below. A specific weight(1–4 g) of chitosan or the chitosan combination was weighed out and incubated with shaking at 37° C. for 2 hours with 6 g soya oil and 10 ml hydrochloric acid (10 mmol/L). The acid was then neutralised and 10 ml phosphate buffered saline (pH 7.4) added. Incubation with shaking was continued for a further 3 hours at 37° C., after which the tubes were centrifuged at 2500 rpm for 30 min. Unadsorbed fat floated on the surface, was aspirated and weighed. This gave the amount of triacylglycerol not bound to the chitosan combination.

Subjects

Seventy four overweight (BMI 25–30 kg/m²) women (19–32 years) were recruited to take part in the study. They gave their written consent after details of the trial had been verbally explained to them and could drop out of the study at anytime they wanted without having to give reason. Ethics approval was obtained from the Joint University/Ministry of Health Ethics committee, Cameroon. Subjects were randomly allocated one of four treatments in a double blinded study. The results are for fifty nine subjects who completed the study. The control group received maize flour, while the other groups received either chitosan, chitosan plus Vernonia glabra (16% w/w) or chitosan plus Cissus quadrangularis (16% w/w). All subjects were required to consume 2 g of the control or test material twice daily before their main meals.

Diet

The subjects were asked not to change their food habits and to maintain their normal diets as much as possible. They kept individual food diaries which were used to analyze food intake using food tables.

Fecal collections and analysis.

Faeces were collected for four consecutive days every other week, in special glass containers and brought daily to the laboratory for storage. All subjects were instructed to bring in their samples as soon as was possible. The feces was weighed and the pH measured. An aliquot (2 g) of the faeces was used for the determination of total lipid using the method described by Folch et al, (1957). The dry matter weight was determined using a homogenate of the total feces collected (3 days drying at 55° C.).

Fecal ash was determined after 48 hours incineration at 500° C. Fecal calcium and magnesium was determined using the modified methods described by SIGMA company. In these methods, the ash was dissolved in nitric acid solution (3N) and the calcium and magnesium assayed spectrophotometrically using arsenazo dye III and calmagite respectively. Total nitrogen was determined by the Kjeldahl procedure. Statistical significance was determined using paired Student's t-test. Results In Vitro Lipid Binding

The in-vitro lipid binding of the different chitosan formulations is shown Table 2. The highest lipid binding was obtained with the formulation CF₁ for each of the two plant powders containing 16% (w/w) of the plant. Cissus quandragularis however bound more (P<0.001) lipid than Vernonia glabia (P<0.01). Other combinations containing Cissus quadrangularis enhanced the binding of soya oil. The binding was however not as high as for the CF1 combination containing 16% (w/w) plant powder.

TABLE 2 The effect of Chitosan formulations on in-vitro lipid (Soja oil) binding (g/g of Chitosan formulation). mean ± S.D Chitosan formulations Plant Powder CF₀ CF₁ CF₂ CF₃ CF₄ V. glabra 13.70 ± 22.04 ± 17.81 ± 12.49 ± 10.44 ± 2.04 2.79** 4.09 4.78 4.9 C. quandragula 13.70 ± 27.80 ± 22.60 ± 18.03 ± 14.89 ± 2.04 0.47** 6.52** 1.17* 2.05 *P < 0.01 **P < 0.001 Food Intake

The average energy and nutrient intake of subjects is given in Table 3. This is similar to the intake of that age group of women in Cameroon.

TABLE 3 The mean of total energy, lipid, carbohydrate, protein, calcium, magnesium and fiber of subject dietary intake mean ± SD ENERGY (Kcal/day) 2346.48 ± 535.55 LIPID (g/day)  92.93 ± 28.00 CARBOHYDRATE (g/day)  367.51 ± 64.54 PROTEIN (g/day)  83.50 ± 15.15 FIBER (g/day)  22.41 ± 5.58 CALCIUM (mg/day)  421.78 ± 243.98 MAGNESIUM (mg/day)  134.58 ± 45.86 Fecal Composition

During the first week of the trial, only the formulation containing Vernonia glabra (16%, w/w) significantly (p<0.05) increased fecal wet weight as well as fecal dry weight (Table 4). On maintaining intake for a longer period (more than one month), chitosan (CF0) significantly reduced the fecal moisture content and increased (p<0.05) fecal pH, while the formulation containing Vernonia glabra significantly (p<0.05) reduced fecal pH Table 4. The ability of chitosan to reduce pH is possibly as a result of the formation of glucosamine in the intestine. At this low pH, there is a modification of bile acid metabolism.

The reduction of fecal pH and moisture content noticed is reversed by the inclusion of Cissus quadrangularis.

This study has shown a negative correlation between the fecal moisture and the fecal pH (r=−0.477) and even between fecal moisture and the root square of fecal pH[(pH)^(1/2)](r=−0.465), P<0.001. So the reduction of fecal moisture can be explained by the increase of the fecal pH.

The reduction of fecal moisture is also dependent on the ash content since fecal moisture is negatively correlated to the fecal ash content (mg/g of FDW) (r=−0.301), P<0.01 (Table 5).

TABLE 5 Correlation between different fecal components Variable r (N = 80) Probability (P) moisture, pH −0.477 P < 0.001 moisture, (pH)^(½) −0.465 P < 0.001 moisture, ash −0.301 P < 0.01 ash, pH +0.248 P < 0.05 calcium, pH −0.221 P < 0.05 moisture, calcium +0.030 N.S ash, calcium −0.069 N.S pH, Nitrogen −0.232 P < 0.05 ash, Nitrogen +0.009 N.S moisture, Nitrogen +0.011 N.S

Chitosan as well as the chitosan formulation containing Cissus quadrangularis significantly (p<0.05) increased the fecal calcium concentration after one month of treatment (Table 6). The formulation containing Veronia glabra however brought about a decrease in the concentration of fecal calcium. It is likely that the increased concentration of calcium in feces is as a result of contribution from the chitosan. There however seems to be a factor in the formulation containing Vernonia glabra that causes an increased retention of calcium. Unlike calcium, magnesium concentrations in the faeces was not altered by any of the formulations (Table 6).

Fermentation of chitosan in the large intestine produces glucosamine which can be absorbed (application in arthritis) by the body. Glucosamine can also bring about an increase in gut pH which favors the absorption of nitrogenous compounds (negative correlation between fecal pH and total fecal nitrogen, r=−0.232; p<0.05). The formulation containing Vernonia glabra however significantly (p<0.05) increased the amount of nitrogen present in the faeces (Table 6). This increase is still significant even when the amounts contributed by the presence of chitosan is taken into consideration. On the other hand, fecal nitrogen is significantly (p<0.05) reduced by the chitosan formulation containing Cissus quadrangularis.

Vernonia glabra therefore seems to play a role in inhibiting the absorption of nitrogenous compounds which will otherwise be favored by an increase in pH.

Chitosan as well as chitosan based formulations significantly (p<0.01) increased the total amount of lipid in the faeces (Table 7). This is as a result of the ability of chitosan to bind lipids in the gut. (It will however be interesting to investigate what happens to the mixture of lipids, chitosan and glucosamine in the large intestine).

These results support the hypothesis that phytochemical substances in some plants can improve the ability of chitosan to bind lipids and contribute to weight loss without negatively altering the calcium and magnesium status of the subject.

The results show that the chitosan only formulations increase fecal pH and cause constipation while CF1.V decreased the fecal pH. These results suggest that the long term intake of chitosan might cause colon cancer while the use of CF1.V can benefit overweight and obese patients.

TABLE 4 The effect of Chitosan formulations on fecal wet and dry weight, pH and moisture Control (n = 20) Chitosan (n = 21) Chitosan + V.g (n = 18) Chitosan + C.q (n = 21) Measures D₀ D_(>30) D₀ D_(>30) D₀ D_(>30) D₀ D_(>30) Fecal wet 165.4 ± 26.4^(a) 187.8 ± 41.5^(a) 185.7 ± 24.6^(a) 180.2 ± 16.7^(a) 178.5 ± 39.0^(a) 264.2 ± 33.^(b)  188.1 ± 28.6^(a) 187.8 ± 82.^(a)  weight(g/d) Fecal dry 26.3 ± 5.3^(a) 28.5 ± 9.8^(a) 29.0 ± 5.3^(a) 28.9 ± 9.7^(a) 28.2 ± 8.2^(a) 36.0 ± 9.4^(b) 28.2 ± 7.7^(a) 27.2 ± 9.4^(a) weight(g/d) Fecal 79.8 ± 4.9^(a) 80.1 ± 5.2^(a) 78.6 ± 5.9^(a) 72.6 ± 6.7^(b) 79.1 ± 4.0^(a) 81.0 ± 4.5^(a) 78.9 ± 3.8^(a)  74.9 ± 6.1^(ab) moisture % Fecal pH  6.9 ± 0.6^(a)  6.8 ± 0.8^(ac)  6.9 ± 0.4^(a)  7.4 ± 0.3^(b)  6.8 ± 0.2^(a)  6.5 ± 0.3^(c)  6.9 ± 0.5^(a)  7.0 ± 0.3^(a) Values are 4-days means ± S.E Values without a common superscript are significantly different (P < 0.05)

TABLE 6 The effect of chitosan formulations on fecal ash, calcium and magnesium and nitrogen Control (n = 20) Chitosan (n = 21) Chitosan + V.g (n = 18) Chitosan + C.q (n = 21) Measures D₀ D_(>30) D₀ D_(>30) D₀ D_(>30) D₀ D_(>30) Fecal ash g/d 2.5 ± 1.1^(a) 3.0 ± 0.9^(a) 2.7 ± 1.4^(a) 5.2 ± 3.7^(b) 3.0 ± 1.3^(a)  3.7 ± 1.8^(ab) 2.8 ± 1.8^(a) 5.4 ± 2.5^(b) Calcium mg/d 100.1 ± 23.7^(a)  117.6 ± 12.3^(a)  104.4 ± 108^(a)   180.3 ± 85.5^(b)  88.4 ± 34.2^(x) 65.1 ± 15.2^(c) 109.4 ± 15.3^(a)  130.1 ± 14.3^(b)  Magnesium 83.5 ± 21.3^(a) 76.5 ± 16.9^(a) 89.6 ± 17.6^(a) 100.5 ± 32.5^(b ) 82.3 ± 11.4^(a) 89.4 ± 14.2^(a) 91.1 ± 21.1^(a) 92.5 ± 12.9^(a) mg/d Nitrogen (N₂) 354.5 ± 128.5^(a) 384.3 ± 194.3^(a) 391.7 ± 133.6^(a) 421.7 ± 355.0^(a) 379.9 ± 170.9^(a) 1039.5 ± 380.6 ± 164.5^(a) 371.1 ± 196.4^(a) mg/d 5411.^(b) N₂-Chitosan 354.5 ± 128.5^(a) 384.3 ± 194.3^(a) 391.7 ± 133.6^(a) 312.9 ± 355.0^(a) 379.9 ± 170.9^(a) 930.7 ± 340.1^(b) 380.6 ± 164.5^(a) 262.3 ± 196.4^(a) N₂ mg/d Values are 4-days means ± S.E Statistical significance is by comparison within a specific measured parameter. Values without a common superscript are significantly different (P < 0.05)

TABLE 7 The effect of chitosan formulations on total lipid excretion Control (n = 20) Chitosan (n = 21) Chitosan + V.g (n = 18) Chitosan + C.q (n = 21) D₀ D_(>30) D₀ D_(>30) D₀ D_(>30) D₀ D_(>30) Total lipid(mg/g)^(a) 73 ± 15^(a) 87 ± 15^(a) 83 ± 16^(a) 163 ± 18^(b)  86 ± 19^(a) 183 ± 12^(b) 88 ± 16^(a) 161 ± 6^(b)  g/d 8.4 ± 3.7^(a) 10.0 ± 4.0^(a)  9.6 ± 4.1^(a) 29.4 ± 14.2^(b) 9.9 ± 4.5^(a) 48.3 ± 9.2^(b) 10.2 ± 3.9^(a)  30.3 ± 13.2^(b) Values are 4-days means ± S.E Values without a common superscript are significantly different (P < 0.01)

EXAMPLE 3

The effect of chitosan based formulations on body composition in overweight women.

Chitosan and chitosan based formulations containing Cissus quadrangularis and Vernonia glabra were administered to sixteen overweight (BMI>25 kg/m²) women on an energy restricted diet supplemented with vitamins and minerals over a period of eight months. There was a significant reduction in the BMI of subjects given chitosan as well as the chitosan based formulations (4 grams per day) containing the plant extracts (16%, w/w), with the most significant reduction observed in subjects who received the chitosan based formulation containing Cissus quadrangularis. A significant reduction in the circulating levels of cholesterol and total triglycerides was observed in all the chitosan based groups.

Materials and Methods

The following combinations were used for the study:

-   -   Group 1. Maize flour—Control group     -   Group 2. Chitosan plus vitamin C     -   Group 3. Chitosan plus vitamin C plus Vernonia glabra     -   Group 4. Chitosan plus vitamin C plus Cissus quadrangularis         Subjects

Thirty two overweight (BMI>25 kg/m²) women (24–36 years) were recruited for the study. They gave their written consent after details of the trial had been verbally explained to them. They could drop out of the trial at any time without need to explain their action. The results reported are for twenty subjects who completed the study. Subjects randomly allocated one of the four treatments above in a double blind study. All subjects were required to consume 2 g of the control or test material twice daily before their main meals.

Diet

The subjects were given a number of possible diets they could follow, which provided a total daily energy intake of 1500 kcal.

Body Mass Index (BMI) and Body Fat Content

The BMI of subjects was measured using an electronic scale and a meter rule attached to the wall. The percentage body fat was determined by using bioelectrical impedance measurements.

Blood Collection and Sampling

Venous blood (20 ml) was collected from the forearm of subjects, and serum prepared from it was stored in 1 ml vials at −70° C. until required.

The concentration of total cholesterol and triglycerides were determined using Sigma kits.

Results

Body Mass Index (kg/m²). Values are Means±Sem.

TABLE 8 D₀ D₇ D₁₅ D₃₀ D₆₀ D₉₀ D₁₂₀ D₁₅₀ D₁₈₀ D₂₁₀ Control 30.61 ± 31.61 ± 29.41 ± 29.21 ± 29.03 ± 29.03 ± 30.04 ± 29.87 ± 29.22 ± 28.69 ± 2.03 2.03 2.42 1.68 1.76 2.34 1.67 1.98 2.10 3.01 Chitosan 28.66 ± 28.60 ± 27.31 ± 26.02 ± 26.03 ± 25.34 ± 27.87 ± 28.02 ± 26.21 ± 26.04 ± 1.78 1.78 2.02 2.01 1.67 1.67 1.87 1.67 2.02 1.53* Chitosan + 29.92 ± 29.83 ± 28.33 ± 26.18 ± 25.87 ± 25.34 ± 25.02 ± 24.98 ± 25.38 ± 24.88 ± Vernonia glabra 2.17 2.18 1.67 1.78 1.23* 1.56* 1.78* 1.82* 1.56* 1.67* Chitosan + cissus 28.43 ± 28.62 ± 28.04 ± 26.44 ± 24.64 ± 23.40 ± 23.55 ± 25.60 ± 24.36 ± 24.31 ± quadrangularis 1.53 1.33 1.89 0.98 1.22** 2.68** 2.67** 3.56 1.78* 1.50* *p ≦ 0.05; **p ≦ 0.01 Conclusions:

Subjects on a daily average energy intake of approximately 1500 kcal, did not show any significant change in BMI. Subjects on the formulations containing Vernonia glabra as well as Cissus quadrangularis had reduced BMIs after being on the formulation for 60 days

TABLE 9 Body fat content (%) D₀ D₇ D₁₅ D₃₀ D₆₀ D₉₀ D₁₂₀ D₁₅₀ D₁₈₀ D₂₁₀ Control 39 ± 9 41 ± 12 39 ± 14 37 ± 12 39 ± 8  37 ± 6  38 ± 8 36 ± 6 38 ± 6 36 ± 6 (37 ± 8)  (35 ± 4)  (33 ± 3)  (32 ± 2)  (31 ± 3)  Chitosan  37 ± 10 38 ± 8  38 ± 6  35 ± 9  34 ± 7  34 ± 6  32 ± 3 35 ± 8 33 ± 6 33 ± 5 (36 ± 8)  (33 ± 2)  (31 ± 2)  (31 ± 2)  (29 ± 2)  Chitosan + 36 ± 9 37 ± 10 36 ± 12 34 ± 8  31 ± 9  29 ± 10 29 ± 8  28 ± 8*  28 ± 8* 28 ± 9 Vernonia glabra (36 ± 6)  (32 ± 3)  (30 ± 2)  (27 ± 2)  (25 ± 3)  (24 ± 3)  Chitosan + cissus 37 ± 8 37 ± 8  36 ± 9  33 ± 8  29 ± 8   24 ± 9**  24 ± 6**  24 ± 7**  23 ± 4**  24 ± 5** Quadrangularis (35 ± 4)  (32 ± 2)  (29 ± 3)  (25 ± 3)  (22 ± 2)  (21 ± 2)  p ≦ 0.05; **p ≦ 0.01 (The figures in bracket represents values for subjects who were on a daily energy intake of 800 kcal rather than 1500 kcal). Conclusion:

There is a significant decrease in total body fat in the groups treated with the chitosan formulations in subjects maintained on a diet of 1500 kcal per day. In subjects maintained on a 800 kcal per day diet, a decrease in body fat was observed in all groups.

TABLE 10 Total Blood Cholesterol (g/L) Day 0 Day 7 Day 15 Day 30 day 60 Control 1.70 ± 0.12 1.50 ± 0.09 1.54  0.18 1.65 ± 0.15 1.58 ± 0.11 Chitosan 1.60 ± 0.06 1.44 ± 0.10  0.73 ± 0.06**  0.92 ± 0.05**  0.84 ± 0.12** Chitosan + 2.07 ± 0.11 1.78 ± 0.10 1.42 ± 0.08 1.37 ± 0.11  1.23 ± 0.30* vernonia glabra Chitosan + Cissus 1.94 ± 0.14  1.19 ± 0.18*  0.85 ± 0.09**  0.81 ± 0.09**  1.01 ± 0.11** quadrangularis *p ≦ 0.05, **p ≦ 0.01. Significant differences are by comparing to the control for each time point. Conclusion:

Chitosan and the chitosan formulation containing Cissus quadrangularis were the most effective in lowering blood cholesterol levels for any given time point. Considering the composition of the formulations containing the plant extracts, it is obvious that there is a component in Vernonia glabra that inhibits the reduction of blood cholesterol levels by chitosan. On the other hand, a component or components present in Cissus quadrangularis may potentate this reduction.

TABLE 11 Total Blood Triglycerides (g/L) Day 0 Day 7 Day 15 Day 30 day 60 Control 1.84 ± 0.08 1.83 ± 0.08 1.76 ± 0.10  1.89 ± 0.09  1.76 ± 0.18  Chitosan 1.26 ± 0.13 1.18 ± 0.05 0.65 ± 0.14** 0.83 ± 0.11*  0.74 ± 0.10** Chitosan + 1.87 ± 0.31  1.19 ± 0.08* 0.82 ± 0.09** 0.73 ± 0.06** 0.68 ± 0.08** vernonia glabra Chitosan + Cissus 1.84 ± 0.32 1.49 ± 0.27 0.62 ± 0.14** 0.84 ± 0.07** 0.70 ± 0.10** quadrangularis *p ≦ 0.05, **p ≦ 0.01. Significant differences are by comparing to the control. Conclusion:

Chitosan and chitosan formulations significantly decreased the circulating concentrations of triglycerides. This is as a result of their ability to bind triglycerides in vitro as well as in vivo. The presence of plant extracts did not seem to have a potentiating effect on the ability of chitosan to bind triglycerides.

EXAMPLE 4

The Effect of Cissus quadrangularis and Vernonia glabra Combination on Blood Lipid Levels

The mixture used in this part of the work had the following composition:

Chitosan 61.8% Vitamin C 19.0% Vernonia glabra powder 5.7% Cissus quadrangularis powder 13.5%

This mixture had a superior lipid binding capacity in vitro compared to other chitosan formulations. containing either Vernonia glabra or Cissus quadrangularis.

In Vitro Lipid Binding Capacity of Mixture

32.6 grams oleic acid per gram of mixture

Effect of Mixture on BMI in Overweight Adults (BMI>25)

TABLE 12 D₀ D₇ D₁₅ D₃₀ D₆₀ D₉₀ D₁₂₀ D₁₅₀ D₁₈₀ D₂₁₀ Control 30.61 ± 31.61 ± 29.41 ± 29.21 ± 29.03 ± 29.03 ± 30.04 ± 29.87 ± 29.22 ± 28.69 ± 2.03 2.03 2.42 1.68 1.76 2.34 1.67 1.98 2.10 3.01 Chitosan 28.66 ± 28.60 ± 27.31 ± 27.02 ± 26.03 ± 28.04 ± 27.87 ± 28.02 ± 26.21 ± 26.04 ± 1.78 1.78 2.02 2.01 1.67 1.67 1.87 1.67 2.02 1.53* Chitosan + 29.92 ± 29.83 ± 28.33 ± 26.18 ± 25.87 ± 25.34 ± 25.02 ± 24.98 ± 25.38 ± 24.88 ± Vernonia glabra 2.17 2.18 1.67 1.78 1.23* 1.56* 1.78* 1.82* 1.56* 1.67* Chitosan + cissus 28.43 ± 28.62 ± 28.04 ± 26.44 ± 24.64 ± 23.40 ± 23.55 ± 25.60 ± 24.36 ± 24.31 ± quadrangularis 1.53 1.33 1.89 0.98 1.22** 2.68** 2.67** 3.56 1.78* 1.50* Chitosan + 28.71 ± 26.83 ± 25.40 ± 23.48 ± 23.47 ± 24.06 ± 23.02 ± 23.98 ± Cissus/ 2.17 1.38 1.43* 1.28** 1.22** 1.33** 0.78** 1.82* Vernonia mixture *p ≦ 0.05; **p ≦ 0.01 Conclusions:

The chitosan formulation containing a mixture of Cissus quadrangularis and Vernonia glabra significantly reduced the BMI of overweight females faster than formulations containing either Cissus quadrangularis or Vernonia glabra. This synergistic effect is possibly as a result of a reduction in the available glucose substrate for use as a fuel (α-amylase inhibition by Vernonia glabra). Fat preferentially used as fuel.

The preferred specific mixture amongst within the scope of the invention, has application because of its effects upon different physiological processes. Preferred applications include the following:

1) Use in the management of obesity, overweight, weight maintenance, slowing down the addition of weight, reduction of bounce back during weight loss and complications resulting from obesity. This includes conditions such as hyperlipidemia, hypercholesteremia and, inability to move freely. 2) Uses in the management of diabetes and complications resulting from diabetes. This includes hyperglycaemia, ketonuria and diabetic coma. 3) Use in controlling gastric acidosis. 4) Use in the relief of constipation.

The above physiological processes are apparently brought about by action of the mixture on one or more of the following factors:

Reduction of fat absorbed by the body; Increases in the amount of fat in faeces Increase of faecal bulk; Reduction of carbohydrate breakdown in vivo; Decrease in acidity of the stomach; Increase in the amount of cholesterol in the faeces;

Reduction of post-prandial blood glucose; and/or Reduction of Body mass index (BMI) and weight.

Inhibition of Salivary and Pancreatic Amylase Activity

Human salivary amylase (Sigma A 0521) and porcine pancreatic amylase (Sigma A3176) were used as starting material. The substrate used was starch and the formation of maltose was used to quantify and measure the activity of the amylase. One unit of activity of the mixture reduced the activity of salivary amylase by 50%, and the activity of pancreatic amylase by 65%.

Decrease of acidity of the stomach Laboratory animals were fed diets containing the mixture (0.5 ml/kg body weight) after an overnight fast.

The content of their stomachs had a higher pH than control animals.

Humans who ingested the mixture produced faeces with a lower pH than control humans who had not ingested the mixture.

Inhibition of Pancreatic Lipase Activity

Pancreatic lipase (Sigma L9780) was used as starting material.

One unit of the mixture is the quantity that will reduce the activity of 0.48 units of lipase by 50%. (One unit of lipase will liberate 1.0 μl of 2-monoglyceride from 1,2-diglyceride per minute at 37° C., pH 8.1). 

1. A method of promoting weight loss in a mammal in need thereof comprising: providing a composition containing an aqueous extract of stems or leaves or stems and leaves of one or more Cissus quandragularis plants to promote weight loss; wherein the composition provided is administered to the mammal to promote weight loss.
 2. The method of claim 1, wherein the composition further comprises one or more compounds that bind(s) to fatty acids.
 3. The method of claim 2, wherein the one or more compounds that bind(s) to fatty acids is chitosan.
 4. The method of claim 2, wherein the composition further comprises one or more amylase inhibiting compounds.
 5. The method of claim 1, wherein the composition is formulated to provide 0.1 ml to 10.0 ml of 50% to 90% (v/v) extract for every kilogram of mammal.
 6. The method of claim 1, wherein the composition provides 0.2 ml to 2.0 ml of extract for every kilogram of mammal.
 7. The method of claim 1, wherein the composition provides 200 mg to 400 mg of Cissus quandragularis to the mammal daily.
 8. The method of claim 1, wherein the composition provides approximately 640 mg of Cissus quandragularis to the mammal daily.
 9. The method of claim 1, wherein the composition promotes weight loss by providing one or more benefits selected from the group consisting of: (a) reducing fats adsorbed by the body, (b) increasing fat in the feces, and (c) reducing carbohydrate breakdown.
 10. The method of claim 1, wherein the mammal is a human.
 11. A method of controlling obesity in a mammal in need thereof comprising: providing a composition containing a fat binding compound and an aqueous extract of leaves and stems of one or more Cissus quandragularis plants; wherein the composition provided is administered to the mammal to promote weight loss.
 12. The method of claim 11, wherein the composition further comprises roots of one or more Vernonia glabra plants.
 13. The method of claim 11, wherein the fat binding compound is chitosan.
 14. The method of claim 11, wherein the composition provides 0.2 ml to 2.0 ml of extract for every kilogram of mammal.
 15. The method of claim 11, wherein the composition provides 200 mg to 400 mg of Cissus quandragularis to the mammal daily.
 16. The method of claim 11, wherein the composition provides approximately 640 mg of Cissus quandragularis to the mammal daily.
 17. The method of claim 11, wherein the composition promotes weight loss by providing one or more benefits selected from the group consisting of: (a) reducing fats adsorbed by the body, (b) increasing fat in the feces, and (c) reducing carbohydrate breakdown.
 18. The method of claim 11, wherein the mammal is a human. 